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mafic unit as an ophiolite, since volcanic arc-type ophio- lites are widely accepted in the literature (Dilek and Furnes 2011, 2014). We now review the characteristics of the Mérida Ophiolite that may be significant in iden- tifying its tectonic setting and its relationship with the Upper Schist-Metagranitoid Unit and explore the peri- Gondwanan evolution model most compatible with the combined data. 9.1. Composition of the mafic rocks The common metagabbros and diabases have signifi- cant compositional variability, since both tholeiitic and calc-alkaline types can be recognized (Figure 5c; Hastie et al . 2007). Both groups can be generated in convergent margin setting and can therefore correspond to supra- subduction zone domains (Figures 5d and 5e; Mullen 1983; Wood 1980). A few samples have compositions close to boninitic types since they are characterized by a marked depletion in incompatible trace elements. Although some diagrams fail to constrain the nature of the magmatic arc involved (Nb/Yb – Th/Yb; Shervais 1982; Pearce 2008, 2014; Figure 6a), it appears to have been peri-continental according to other indicators (La/ Yb – Th/Nb diagram; Hollocher et al . 2012; Figure 6c). A peri-Gondwanan magmatic arc is also supported by the characteristics of the siliciclastic series deposited within the arc system (Rojo-Pérez et al . 2019, 2021; Fuenlabrada et al . 2020) and by those of the Ediacaran magmatism itself (Bandrés et al . 2004; Sarrionandia et al . 2020; Rojo-Pérez et al . 2022). There is also some uncer- tainty about the proximal or distal character of the area where the mafic magmatism was generated in relation to the trench (Ti – V diagram; Shervais 1982; Pearce 2014; Figure 6b). However, the composition of the mafic rocks normalized to N-MORB is characterized by negative Ta + Nb, Hf + Zr, and Ti anomalies and positive Sm anomalies, which favours a proximal SSZ-type setting (Figure 6d; Pearce 2014). Hence, the composition of the mafic rocks clearly indicates that they were generated in an SSZ setting, probably of a proximal type, but it does not allow, by itself, distinction between a fore-arc, back-arc, or intra-arc domain. 9.2. Composition of the felsic rocks There is more clarity about the tectonic setting of the small bodies of tonalitic metagranitoids that occur within the ophiolite, since their composition is charac- teristic of granitic rocks generated in typical volcanic arcs Figure 15. P-T path deduced for sample 117,350 (garnet amphibolite from the Mérida Ophiolite). Stability domains for garnet rim compositions are shown (Grs, Alm, SPS, Prp) as well as average composition of plagioclase. See additional explanations in the text. INTERNATIONAL GEOLOGY REVIEW 23 Mérida Ophiolite (SW Iberia)